After the defeat of Senator Bernie Sanders, leading progressive activists faced a difficult choice: Support Joe Biden’s “unity task forces,” announced last month, and compromise in the hopes of winning concessions, or continue a likely doomed rearguard action.

Some have chosen to fight on. “You’re either for Medicare for All or you’re not. You’re for free college or you’re not,” Kyle Kulinski, the host of a popular progressive YouTube show, wrote on Twitter. “You don’t need a fucking task force. It’s a show to placate the left.”

But many of Sanders’s most fervent advocates have decided to give peace a chance. Eighteen top Sanders supporters and progressive activists, including more than a few harsh critics of Biden, accepted appointments to the task forces. That’s a departure from the uncompromising caricature of Sanders’s supporters painted during the primary. It’s also a tough position to be in. How do activists win concessions from a candidate they were railing against just a few weeks ago? And how do they bring their fellow Berners on board with the nominee while maintaining their progressive bona fides?

I asked nine of the Sanders-supporting appointees to Biden’s task forces about the kind of influence they hope to have over his presidential platform. They see some opportunity to move the presumptive nominee left. But they know they won’t get the high-reaching progressive agenda they’ve been fighting for.

The Sunrise Movement, which gave Biden an F grade for his climate agenda, has so far refused to endorse the former vice president. Still, Varshini Prakash, the group’s leader, said she is eager to serve on the climate panel. “When people have asked me, ‘How do you know that this won’t be lip service?’ my answer is, ‘I don’t,’” Prakash told me last week.

Her organization is dedicated to making the Green New Deal a reality, regardless of the Democratic Party’s nominee, she said, referencing the legislative proposal that would involve sweeping reforms to address climate change and economic inequality. When I asked Prakash what, specifically, she plans to bring up in her task-force meetings, she said she’ll urge Biden’s campaign to do three things: shorten its timelines to enact urgent climate policy, add an environmental-justice component to his platform, and hold fossil-fuel companies accountable for their harm to the environment and for disseminating misinformation. “I don’t expect to get everything that I want, but I’d expect to be listened to and engaged in principled debate about these things,” she said.

Several of the appointees I spoke with have real concerns about the efficacy of the project. The whole thing could still be a ruse meant to create the appearance of open-mindedness on the part of the Biden campaign, some said. At the same time, they told me, the panels present an opportunity—maybe the only one—for progressives to weigh in on the policy agenda for the next four years. Even more crucial, they said, is presenting a united Democratic front to take down Donald Trump.

“I would feel like a personal hypocrite if I didn't seize the chance to make a difference,” said Darrick Hamilton, the executive director of the Kirwan Institute for the Study of Race and Ethnicity at Ohio State University and a key adviser to Sanders on issues of racial inequality. “I would be derelict in my responsibility.”

Sanders, who popularized the idea of Medicare for All in his 2016 presidential bid, has appointed three fervent Medicare for All advocates to Biden’s health-care task force: Representative Pramila Jayapal, the physician and former Michigan gubernatorial candidate Abdul El-Sayed, and Donald Berwick, a former administrator of the Centers for Medicare and Medicaid Services during the Obama administration. Biden opposes Medicare for All and instead has argued for a public option and endorsed lowering the age of Medicare eligibility from 65 to 60.

El-Sayed, the former executive director of the Detroit Health Department, has been critical of the former vice president’s health-care position. Still, El-Sayed agreed to join the panel. “We probably won’t be getting the full Medicare for All package. But I do know that what we will put together is so much better than what we have right now,” said El-Sayed, who told me that he hopes the task force can reach a consensus on how to expand health-insurance coverage and address the high price of prescription drugs. Biden is a better option than Trump, El-Sayed said, even if progressives don’t get the policy outcomes they’ve fought so hard for. “Even if you can’t score a touchdown, you can get three points in a field goal.”

Perhaps the reason so many Sanders backers were willing to join the task-force effort is that Sanders asked them to. Before the appointees were announced, the Vermont senator gathered them all on a conference call to assure them of the unity project’s authenticity. This experience would be a genuine attempt to learn from one another, he promised; progressives would be listened to, and their ideas would help shape the nominee’s platform. It’s a huge opportunity, in other words. If task-force members can push the former vice president left on a handful of policy issues, they have a better shot of enticing progressives to support him in November. But if, after several weeks, their input hasn’t had any influence over Biden’s agenda, it’s hard to overstate how incensed the left will be.

The pressure is on. “It’s daunting,” Stacey Walker, a co-chair of Sanders’s campaign in Iowa and member of the criminal-justice task force, told me. “If at the end of six weeks there has been no substantive movement in the material policies that the vice president is advocating for, we will have our answer then.”

Progressives don’t have a lot of other options. “We can either throw our hands up and refuse to try to shape the debate,” Walker said, “or we can do our very best to influence these policies right now and gear up and continue to organize for the next battle.”

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